Until taxonomic revision in 1999,[2]Mannheimia spp. were classified as Pasteurella spp., and infections by organisms now called Mannheimia spp., as well as by organisms now called Pasteurella spp., were designated as pasteurellosis. The term "pasteurellosis" is often still applied to mannheimiosis, although such usage has declined.

Animals

P. multocida causes numerous pathological conditions in domestic animals. It often acts together with other infectious agents, like Chlamydiae, Mycoplasmae and viruses. Environmental conditions (transportation, housing deficiency, and bad weather) also play a role.

The following diseases are considered caused by P. multocida, alone or associated to other pathogens:

Shipping fever in cattle and sheep. ("Shipping fever" may also be caused by Mannheimia haemolytica, in the absence of P. multocida,[3][4] and M. haemolytica serovar A1 is known as the most common cause of the disease.[3] The pathologic condition commonly arises where the causative organism becomes established by secondary infection, following a primary bacterial or viral infection, which may occur after stress, e.g. from handling or transport.[4])

Treatment

As the infection is usually transmitted into humans through animal bites, antibiotics usually treat the infection, but medical attention should be sought if the wound is severely swelling. Pasteurellosis is usually treated with high-dose penicillin if severe. Either tetracycline or chloramphenicol provides an alternative in beta-lactam intolerant patients. However, it is most important to treat the wound.